The present invention relates to an automatic freight stacking or loading apparatus suited for use in a dispatching or shipping system which is capable of loading or stacking freight articles of different configurations such as those to be dispatched from a factory operating on a mass-production basis, air cargo, parcels or packages for home delivery onto transportation means such as containers, pallets or the like within a relatively short time.
There are freight dispatching or shipping systems of two different modes or types mentioned below.
Type 1: Freight articles to be dispatched are loaded or stacked in accordance with a shipping schedule as in the case of the freight shipping system adopted in a factory operating on the mass-production basis, wherein the number of transportation means such as container, pallets or the like which are to be delivered in a day as well as the number, size and other factors of freight articles to be stacked or loaded on each of the transportation means are predetermined and entered in the shipping schedule.
Type 2: A shipping system in which freight articles are determined in respect to the size, the number and other factors only after the articles have arrived at the system, whereupon they are loaded or stacked on the transportation means within a short time. The shipping system of this type is adopted in a freight distributicn center.
In connection with transportation of knockdown parts of automobiles and air cargo, by way of example, there arises increasingly a demand for automating work or operation for loading articles of freight or cargo on the transportation means such as pallet, container or the like. As the equipment for automatically stacking freight articles on the transporting means, there have been known an autopalletizer and a palletizing robot (also referred to as robot palletizer). As to the palletizing robot, reference may be made to articles "Effort in Development of Palletizing Robot" by Okura Transport Machine Co. and "Palletizing Robot 500" by Mizutsu and Ohtoshi, presented in "'83 Industrial Robot" published August, 1983 by Industrial Research Agency in Japan.
However, the hitherto known autopalletizer and palletizing robot can only load the articles of a same size, configuration and material on a given pallet. Accordingly, in view of the fact that there is an increasing tendency for transportation of numerous types of articles each in a reduced amount, the conventional palletizing robot suffers a great disadvantage in that it cannot handle the articles in the case where many different kinds of freight articles are to be loaded or stacked on one and the same pallet.
More specifically, in the case where a variety of the freight articles of different sizes are to be automatically loaded on one pallet by means of the conventional loading machine such as the palletizing robot, there arise serious problems mentioned below.